Normal eGFR by Age
How filtration declines gradually over the decades.
Medically reviewed by Dr. Rishi Kumar Kafle, MBBS, MD, FASN · Last reviewed June 2026
eGFR declines by roughly 1 mL/min/1.73m² per year after about age 40. A gradually lower value in an older adult is often a normal part of ageing rather than a sign of disease.
Typical eGFR by Decade
| Age band | Typical eGFR |
|---|---|
| In your 20s | ~99 |
| In your 30s | ~99 |
| In your 40s | ~94 |
| In your 50s | ~88 |
| In your 60s | ~85 |
| In your 70s | ~78 |
| In your 80s | ~70 |
These are population averages; individual values vary with health, build, and other factors. A result a little above or below the figure for your decade is common and, on its own, rarely a concern — the table is for context, not a target to match exactly.
Why eGFR Falls With Age
The number of working glomeruli and overall blood flow to the kidneys both decrease with age, so filtration slowly drops. Because of this, the CKD threshold of 60 is read in context: a value just below 90 in an older adult may be normal ageing, while a steadily falling trend deserves attention. Explore a single decade, such as eGFR in your 70s.
The CKD-EPI 2021 equation already builds this expected decline into its maths through a small age adjustment, so the result you get from the eGFR calculator is not penalising you for being older — it is reporting the filtration your blood test supports. What matters more than the single number is the direction of travel from one year to the next.
Normal Ageing vs Kidney Disease
The key question is whether a lower eGFR reflects ordinary ageing or something that needs follow-up. Three signals help tell them apart:
- The trend. A value that has been stable for years is reassuring; one that is falling faster than about 1 mL/min/1.73m² per year is worth a closer look.
- Albuminuria. Protein leaking into the urine — measured by an albumin-to-creatinine ratio — points toward kidney damage rather than age alone.
- Other findings. Blood pressure, diabetes, and changes on imaging all shape how a borderline value is interpreted.
An older adult with an eGFR in the 60s, a stable trend, and no albuminuria is usually showing normal ageing. The same number that is dropping year on year, or that comes with protein in the urine, is read differently. This is why the 60 cut-off is never applied in isolation in an older person. For values that have clearly fallen below range, see what a low eGFR means.
How the Decline Is Tracked Over Time
Because eGFR drifts down slowly, a clinician usually looks at a series of results rather than one. A handful of readings over months to years shows whether kidney function is holding steady or sliding. A loss of a point or two per year is expected with age; a steeper slope, or a sudden drop, prompts further tests. Keeping a record of your past values — and comparing each new result with the normal range for your age — is the most useful thing you can do with this number.
Why There Is No Single “Normal for My Age” Number
The figures in the table are population averages, not targets you should hit. Two healthy people of the same age can have eGFR values that differ by a fair margin because of build, muscle mass, sex, and everyday factors like recent diet or hydration. The averages are useful for putting your result in context — they show that a value in the 70s or 80s is unremarkable for an older adult — but your own normal is best judged against your previous readings rather than a single age-based figure. A clinician interprets the number the same way: in context, never in isolation.
How Much eGFR Falls Each Decade
After the adult plateau, the decline is gradual and fairly steady. From around age 40, eGFR drops by roughly one point a year on average, which adds up to about ten points a decade. That is why the typical value slides from near 99 in the 20s and 30s down toward 70 by the 80s. The pace is not the same for everyone — blood pressure, diabetes, and overall health all influence how quickly filtration falls — but the broad pattern is consistent enough that an age-adjusted view is built into how results are read. A value that tracks this expected slope is usually ordinary ageing; one that falls faster is what draws attention.
eGFR by Age in Children and Young Adults
The CKD-EPI 2021 equation on this site is built for adults. In children, filtration is estimated with a different, paediatric method, and the “normal” values differ because kidney function is still maturing. By early adulthood, eGFR has reached its adult plateau — typically near 99 in the 20s and 30s — and the gradual decline of roughly a point a year only begins later, from around age 40. So the age effect described here applies to the adult years, and the steeper changes seen at the extremes of life are handled separately.
Why Age Alone Does Not Define Kidney Disease
It would be simpler if a fixed eGFR meant the same thing at every age, but filtration that is perfectly normal for an 80-year-old would be unexpected in a 25-year-old. This is the reason guidelines stage chronic kidney disease by the eGFR value together with evidence of kidney damage, rather than by age. An older adult is not labelled with kidney disease simply for having an age-appropriate decline; the label depends on whether there is albuminuria, a falling trend, or another marker of damage on top of the lower number.
Check Your Own eGFR
Compare your result with the eGFR normal range, learn what a low eGFR means, or calculate yours with the eGFR calculator. If your value is lower than the average for your decade, look at the trend across past results and check whether a urine albumin test is in range before drawing any conclusion — a stable value with no albuminuria is usually normal ageing, and any concern is best discussed with your clinician.